In the last few years, urban bike sharing has popped up all across the United States: in cities like Boston, New York, Washington D.C., Miami, San Francisco, and Chicago among others. Finally Seattle is getting it's first bike sharing program, Pronto Cycle Share, today. The program, operated by Portland-based Alta Bicycle Share, opens with 500 bikes distributed to 50 stations throughout downtown and central Seattle, with many near grocery stores. Stations will hold between 12 and 20 Arcade Cycles. There are short term passes available: 24 hour and 3-day passes ($8 and $16 respectively), with an annual membership starting at $85. Trips under 30 minutes are unlimited; after that there are additional usage fees. Riders can borrow free helmets, with pick up and drop off at every kiosk. And there will be automated helmet vending machines, but they aren't ready yet. For now, it's an honor code system. And yes, the helmets will be sanitized. Alaska Airlines is the major brand sponsor, at $2.5 million for five years. So what's next? There are plans to expand to the Central District in 2015. More info about Seattle's new bike share program on Pronto's website.